1. Field
Embodiments of the present invention relate to a luminance correcting system and method for an organic light emitting display.
2. Description of Related Art
An organic light emitting display is a type of a flat panel display (FPD) in which an organic compound is used as an emission material. The organic light emitting display has high luminance and color purity, is thin and light, may be driven by low power, and is expected to be useful to various display devices, such as a portable display device.
The organic light emitting display generates data signals having voltages in accordance with respective gray levels based on a reference gamma voltage, and displays an image corresponding to the data signals. Due to variations in manufacturing processes, the luminance components of completed products may be different from a target (e.g., intended) luminance.
When the luminance of a completed product does not reach a target value, the product is determined to be defective. Therefore, it is necessary to correct the measured luminance components of FPDs for the completed products to display the target luminance.
When only the luminance of the organic light emitting display is corrected, due to differences in the efficiency of organic material among differently colored pixels (e.g., a red pixel, a green pixel, and a blue pixel), white balance may deteriorate. Therefore, to solve such a problem, color coordinates may be corrected together with luminance.
However, conventionally, correction of the luminance and the color coordinates is performed only on a reference gray level (e.g., a predetermined reference gray level), and an offset value generated during the correction is directly applied to the remaining gray levels. In this case, correction close to the target value is performed on the reference gray level. However, a difference between luminance and color coordinates and the target value increases in the remaining gray levels, in particular, at gray levels further from the reference gray level.
In addition, the efficiency of the emission organic material of each color may vary with different panels. Therefore, the offset values of the respective colors may be different from each other.
However, correction performed without reflecting the difference in the offset values of the respective colors may generate a phenomenon in which specific colors (e.g., reddish, greenish, and/or bluish hues) may be pronounced in the gray levels (e.g., low gray levels) further from the reference gray levels.